Analysis of a dynamic behavior of the E3 ubiquitin ligase in the endoplasmic reticulum

2014 Fiscal Year Final Research Report

• Project/Area Number: 25870312
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Functional biochemistry; Cell biology
• Research Institution: Nagoya University
• Principal Investigator: NAKATSUKASA Kunio 名古屋大学, 理学(系)研究科(研究院), 助教 (90547522)
• Project Period (FY): 2013-04-01 – 2015-03-31
• Keywords: 小胞体 / タンパク質 / 品質管理機構 / ユビキチン / 分解

Outline of Final Research Achievements

Inactivation of Cdc48p/p97 stalled retrotranslocation and triggered formation of a complex that contains the 26S proteasome, Cdc48p/p97, ubiquitinated substrates, select components of the Hrd1 complex, and the lumenal recognition factor, Yos9p. We proposed that the actions of Cdc48p/p97 and the proteasome are tightly coupled during ERAD. Our data also support a model in which the Hrd1 complex links substrate recognition and degradation on opposite sides of the ER membrane. Based on these results, we performed in vivo site-specific crosslinking experiments. Non-natural photo-reactive amino acids were incorporated into Hrd3 in yeast to detect cross-linked Hrd1. Although we could detect some cross-linked products with Hrd3, it is currently unclear if these are Hrd1-Hrd3 crosslinked products. We are now trying to scale up the system to better detect Hrd1. In addition, we are analyzing a role of the transmembrane domain of Hrd3 especially under the stress conditions.

Free Research Field

分子細胞生物学